Search results for "General Agricultural and Biological Sciences"
showing 10 items of 1320 documents
Thermostats: Modeling non-equilibrium dynamics
2012
Flux-limited diffusion equation
2013
Новое зкспериментальное подтверждение для ядра8Не
1972
In this work we present the analysis and interpretation of an event, consistent with the production and subsequent decay of the exotic nucleus8He, found in the study of K− interactions with nuclear-emulsion nuclei at different energies.
Perturbations of the classical Lotka-Volterra system by behavioral sequences
1995
The complexity and the variability of parameters occurring in ecological dynamical systems imply a large number of equations.
Breaking the temperature-size rule: Thermal effects on growth, development and fecundity of a crustacean from temporary waters
2013
The temperature-size rule (TSR) is a well-established phenomenon to describe the growth response of ectotherms to temperature by which individuals maintained at low temperatures grow more slowly, but attain a larger size upon maturity. Although there are adaptive and non-adaptive theories about the plasticity of body size in response to temperature, these cannot be applied to all ectotherms, and little is known about the changes in growth and development rates through ontogeny. The ostracod species Heterocypris bosniaca, an inhabitant of freshwater temporary ponds, was used to examine the growth and development rates of its nine growth stages and female fecundity at four different temperatu…
Identification of the Weevil immune genes and their expression in the bacteriome tissue
2008
Abstract Background Persistent infections with mutualistic intracellular bacteria (endosymbionts) are well represented in insects and are considered to be a driving force in evolution. However, while pathogenic relationships have been well studied over the last decades very little is known about the recognition of the endosymbionts by the host immune system and the mechanism that limits their infection to the bacteria-bearing host tissue (the bacteriome). Results To study bacteriome immune specificity, we first identified immune-relevant genes of the weevil Sitophilus zeamais by using suppressive subtractive hybridization (SSH) and then analyzed their full-length coding sequences obtained b…
Flavonoids of honey and propolis : characterization and effects on hepatic drug-metabolizing enzymes and benzo(a)pyrene-DNA binding in rats
1996
The influence of dietary sunflower honey, propolis, and a flavonoid extract of propolis was examined on drug-metabolizing enzyme activities in rat liver and on microsome-mediated binding of benzo[a]pyrene to DNA. Characterization of flavonoids present in sunflower honey and propolis was achieved in order to assess the relative effects of different components of honey and propolis. Honey and propolis contained the same major flavonoids, pinocembrin, chrysin, galangin, and pinobanksin. The concentration of flavonoids was higher in propolis. Sunflower honey produced no significant changes on phase I and phase II enzyme activities and no modification of in vitro binding of benzo[a]pyrene to DNA…
Disentangling temporal patterns in our perception of the fossil history of gymnosperms
2012
By taking gymnosperms as a case study, this article evaluates the perception of plant life history from the fossil record to test the biases associated with the time-dependent aspects of the taxonomy, following a stepwise modelling procedure based on two divergent sets of time units. The idea that the effects of the temporal component of paleobiological inference need to be evaluated to remove any possible bias in our interpretation and perception of plant evolution based on analyses of large-scale data sets is investigated. The results reveal important differences in our perception of the tempo of gymnosperm evolution and how it is biased in terms of time unit length due to the loss of inf…
An integrative review of the enjoyment of sadness associated with music
2018
The recent surge of interest towards the paradoxical pleasure produced by sad music has generated a handful of theories and an array of empirical explorations on the topic. However, none of these have attempted to weigh the existing evidence in a systematic fashion. The present work puts forward an integrative framework laid out over three levels of explanation – biological, psycho-social, and cultural – to compare and integrate the existing findings in a meaningful way. First, we review the evidence pertinent to experiences of pleasure associated with sad music from the fields of neuroscience, psychophysiology, and endocrinology. Then, the psychological and interpersonal mechanisms underly…
Spatial distribution of two maternal messengers encoding two sea urchin cell surface proteins
1993
We have localized, byin situ hybridization, two messengers, called bepl and bep4 (butanol extracted proteins), coding for cell surface proteins, involved in cell interaction, in sections of eggs of the sea urchinP. lividus. These maternal RNAs are spatially distributed in a gradient with a maximum at one pole of the egg. These results represent the first demonstration of the existence of a gradient of informational molecules in the sea urchin egg,i.e., the biological material for which the gradient theory was first proposed.